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Chemiluminescence from thermal decomposition of dibenzal diperoxide in the presence of aromatic fluorescent compounds was studied. The emitting species was identified as the lowest excited singlet state of the

The thermal fragmentation of organic compounds is described using a technique in which the sample is coated on a ferromagnetic conductor. This conductor can be reproducibly heated to an accurately defined temperature (Curie point) in 20 to 30 milliseconds. Techniques are described to study fragmentation mechanisms.

Lipophilic maprotiline metabolites were extracted from human urine and animal excreta, with or without prior enzymic hydrolysis, purified by repeated t.l.c. and their structures determined by u.v., n.m.r. and mass spectrometry. Urine from patients under treatment with maprotiline contained the isomeric phenols, 2- and 3-hydroxymaprotiline, the 2,3-dihydrodiol, and an alcoholic metabolite, besides smaller quantities of the corresponding N-demethylated compounds. In dog urine and/or faeces the same products of aromatic hydroxylation were present as in human urine and in addition 3-hydroxy-2-methoxymaprotiline; alcohols were not detected. The only metabolites identified in rabbit urine and rat bile were 3-hydroxy- and 3-hydroxy-2-methoxymaprotiline.

Ion cyclotron single and double resonance techniques have been used to study the positive ion-molecule chemistry of nitromethane and nitroethane. The reactions in nitromethane can be divided into four classes:(1) proton transfer to nitromethane; (2) methyl cation transfer from CH3NO+ and CH3N02+ to nitromethane;(3) NO+ transfer from CH2N02+; and (4) an unusual O" abstraction by methyl cation. The reactions in nitroethane are (1) proton transfer to nitroethane from QHs'1", H8CN+, and GHs"1"; (2) NO+ transfer from H2N02+; and(3) a probable dissociation of protonated nitroethane into H2N02+ arid C2H4. Deuterium and nitrogen-15 isotopic labeling were used to obtain information oh the mechanisms of the reactions. Proton transfer reactions were used to determine that the proton affinity of nitromethane is 180 ± 4 kcal/mol while that of nitroethane is 185 ± 4 kcal/ mol. These values correspond to /7((0 3 2 +) = 168 and //(( 5 02 +) = 157 kcal/mol. The mass spectra of the nitroalkanes are unusual in that the major peaks are hydrocarbon ions. Only the nitromethane ion is stable with respect to decomposition into an alkyl cation and nitrogen dioxide;(1) (a) Varían Postdoctoral Fellow, 1968-1969